title: Cell kinetics of PHA-activated lymphocytes are slowed by prolonged hypertonic stress.
abstract: The effect of prolonged exposure to a hypertonic medium on human lymphocytes during mitogenic stimulation with phytohemagglutinin was investigated. The process of chromatin decondensation during the first 24 hrs stimulation (G0 to G1 transition) and the changes in kinetic parameters and the occurrence of chromosome aberrations from 48 hrs to 72 hrs of stimulation were studied. In HT medium, lymphocyte transition from G0 to G1 was slowed; there were fewer S-phase cells, after 48 hrs PHA stimulation, whereas after 72 hrs the resistant cells showed the same frequency of S-phase cells as the controls. The mitotic index was always smaller, and the frequency of G0/G1 cells larger. No significant increase in the frequencies of chromosome aberrations were found. These findings suggest that human peripheral lymphocytes can survive and grow in a hypertonic medium; chromosome damages, if not repaired, may be lethal, and only lymphocytes with normal karyotypes can survive for long times in the HT medium, although with modified kinetic characteristics.
authors.affiliation: Dipartimento di Biologia e Genetica per le Scienze Mediche, University of Milano, Italy.
authors.forename: A M
authors.initials: AM
authors.lastname: Fuhrman Conti
authors.forename: R
authors.initials: R
authors.lastname: Tori
authors.forename: E
authors.initials: E
authors.lastname: Ronchetti
authors.forename: L
authors.initials: L
authors.lastname: De Grada
authors.forename: C
authors.initials: C
authors.lastname: Pellicciari
authors.forename: M G
authors.initials: MG
authors.lastname: Manfredi Romanini
mesh_terms: D002453:Cell Cycle / Q000187:drug effects; D002470:Cell Survival / Q000187:drug effects; D002869:Chromosome Aberrations; D004305:Dose-Response Relationship, Drug; D005434:Flow Cytometry; D006801:Humans; D006982:Hypertonic Solutions; D007091:Image Processing, Computer-Assisted; D007621:Karyotyping; D007700:Kinetics; D008213:Lymphocyte Activation / Q000187:drug effects* / Q000502:physiology; D008214:Lymphocytes / Q000166:cytology* / Q000187:drug effects / Q000502:physiology; D008938:Mitosis / Q000187:drug effects; D010835:Phytohemagglutinins / Q000494:pharmacology*; D012965:Sodium Chloride / Q000494:pharmacology*
chemical_list: D006982:Hypertonic Solutions; D010835:Phytohemagglutinins; D012965:Sodium Chloride